Uploaded by renjith_reghunath

5 simple steps to total

advertisement
5 simple steps to total valve integrity — Pipelines International — The international pipel... Page 1 of 3
A Great Southern Press Site
HOME
LATEST NEWS
MAGAZINE ISSUES
EVENTS
PHOTO GALLERY
5 simple steps to total valve
integrity
JASON CHISHOLM, SEALWELD CORPORATION
Pipelines International — December 2009
Careful handling and storage of valves
prior to installation, as well as following
correct procedures during construction
and commissioning, ensures a more
efficient and safe pipeline, with less
chance of lost production and failed
isolations. This article outlines five steps
to follow for a healthy valve.
1. Selecting the right valves
There are many valve manufacturers and
valves for any type of production,
temperature, pressure and service condition
can be found. Of these makes and styles
there is a wide range of feature options to
choose from, such as full or reduced port,
floating or trunion-mounted ball, rising or non-rising stem gate.
When selecting a crucial component like a mainline block valve, it is best to
consider the service conditions. What is the likelihood of the valve seat seals being
worn enough to cause significant leakage due to continued dry cycling or the
presence of an abrasive like construction debris, black powder or sand? For
instance, a metal-seated plug valve would suit a mainline block cross-over
assembly application better than a soft-seal ball valve. Due to line purging and
throttling, damage can easily occur on the soft-seat seals of a ball valve, whereas
metal-seated plug valves are designed to resist seat wear in these conditions.
Many manufacturers claim to produce valves that do not require lubrication and,
hence, do not include a seat sealant system to inject lubricant or emergency
sealant. Every valve will eventually leak if not properly maintained and the
operator’s ability to maintain production or to isolate a pipe section could depend
greatly on sealing one leaking valve.
2. Storage and handling
Valve care is often neglected before initial installation. Often large diameter block
valves are stored on a dusty construction site with no end covers or alternative
protection from airborne contaminants. Rarely is the internal sealing integrity of
the valve taken into consideration by construction crews whose number one
concern is its timely installation.
Likewise, the improper transportation of the valve itself should be of paramount
concern to project managers. Any rough handling of the valve could cause the
ball or gate to ‘creep’ out of its seat, exposing the seat ring and body cavity to
debris contamination. Any opportunity to prevent contamination of the valve
assembly will increase the likelihood of achieving a positive seat seal test once
installed.
3. Upgrading
Once the valve design that best suits the operating conditions of the pipeline has
been chosen, one of the most important steps is to outfit the valve with the
proper internal check valves, sealant injection fittings, body vent/drain fittings,
packing injectors, and riser lines (if required). The only chance at maintaining the
sealing integrity of the valve depends on the ability to inject synthetic lubricants
and sealants into the seat and stem areas of the valve. It only takes one cycle of a
contaminated valve to completely destroy the highly sensitive soft seals inside the
seating area.
Typically, these upgrades are overlooked during the design phase as future wear
and tear is rarely taken into account. Specifying 3/8 inch riser lines, opposed to
the more popular and slightly cheaper ¼ inch riser lines, enables service
technicians a much greater chance of injecting a heavy sealant faster if leakage is
occurring in the seat area and a seal must be achieved. Likewise for injection
fittings, a threaded cage design is more likely to withstand the injection pressures
of heavy emergency sealants than a crimped cage design, which can fail under as
little as 3,000 psi (20,700 kPa). Studies have shown that threaded cage style
fittings can withstand injection pressures of well over 50,000 psi (344,700 kPa).
Valve maintenance technicians rely on the ability to blow-down the valve body
cavity to create pressure differentials across leak paths in order to ‘draw’ sealants
into the required areas. Technicians are often faced with servicing valves of up to
ADVERTISING
ABOUT
Subscribe to
the magazine
now!
Or you can
read the
magazine
online.
TOP NEWS ARTICLES
1. APLNG pipeline contract awarded
2. Independent panel recommends
Mackenzie pipeline proceeds
3. FERC gives Ruby Pipeline green
credentials
4. Australian pipeline research
centre appoints CEO
CONTACT
username
Login
Search the site
Go
You may also like to try the Advanced Search.
Enter your details here to subscribe to the free
Pipelines International Update.
First name
Last name
Company name
Phone number
Email address
Join
 Please check here to confirm your subscription.




5. Pemex plans Tamazunchale-San
Luis de la Paz pipeline tender
6. Pipelines International December
edition online!
7. Bolivia – Argentina pipeline
extension approved
8. Bidding opens on Denali Pipeline
9. Russia and Belarus continue to
negotiate Druzbha pipeline deal
10. Staying ahead of the pipeline
professional pack; technical training
courses on offer in 2010
TOP MAGAZINE ARTICLES
1. Pipeline development in the land
of the free — BJ Lowe, Clarion,
Houston, USA and Lyndsie Mewett,
Associate Editor
2. Going with the flow: internal
coatings (expanded version) — By
Ian Robinson and Craig Thomas, 3M
United Kingdom plc (formerly E
Wood Ltd)
3. Assessing the environmental
impacts of pipelines — By Dr Janet
Swan, Environment Director, RSK
4. TransCanada supersizes Keystone
project
5. Pipeline link constructed in central
Australia
6. Protecting pipelines in mountain
areas — Vlad Popovici, Bredero
Shaw, Toronto, Canada
7. Australian industry gathers in
northern Australia
8. IP Pipeline moves forward after
much discussion
9. Trans-Mediterranean Pipeline
10. Pipes & People
FOLLOW US ON TWITTER!
Latest Twitter updates:
• Technip wins West
African subsea contract
#Pipelines
http://bit.ly/75jhKp 4 days ago
• RT @AussiePipeliner: APIA
Convention attendees love pipelines!
See the video at
http://tinyurl.com/yeetqfr #pipeline
4 days ago
• Subsea 7 has successfully
completed the Girassol Pipeline
Repair Project, located offshore
northwest Angola #Pipelines
http://bit.ly/8skwSI 6 days ago
http://pipelinesinternational.com/news/5_simple_steps_to_total_valve_integrity/009339/
1/26/2010
5 simple steps to total valve integrity — Pipelines International — The international pipel... Page 2 of 3
60 inch inner diameter that are outfitted with ¼inch body vent ports. This is
hardly an ideal situation as the drain port will not be able to vent enough pressure
to create the kind of differential that is required to deliver the sealant to the areas
that need it the most. Many pipeline operators are beginning to specify full-port
ball valves in place of body vent fittings on large diameter valves for this reason.
4. Inspecting and commissioning
Of any step taken toward ensuring that a pipeline runs efficiently and safely, valve
commissioning is the most crucial. A case in point involves the resurrection of
three brand new 36 inch buried mainline block valves due to the complete
washout of seat seals during nitrogen purging. The cause: no lubricant in the seat
sealant system or seat ring groove.
As a result of valve installation, construction debris becomes trapped inside the
pipe where the butt ends are welded. Once installed, the purging process pushes
the construction debris against the ball and into the gap between the seat ring
and the sealing face. At this point during the aforementioned construction
project, had any lubricant been injected into the valve, it would have pushed
enough of the debris out and away from the sealing area and minimal damage
would have occurred. Instead, the valve was dry cycled and so severely damaged
to the point that it required replacement before the pipeline section could be
brought online.
Want to see the latest? Follow
Pipelines International on Twitter.
SOMETHING TO TELL US?
Do you have something to tell
Pipelines International? Submit your
news or information here.
MEDIA KIT
Download the
Pipelines
International
Media Kit (PDF).
Leak Detectors & Testers
Cost effective leak detection
Alternate to helium and air testing
www.sensistorusa.com
Expansion Joints
All Metal & Rubber Expansion
Joints Flexicraft Flexible Pipe
Solutions
www.FleXicraft.com
DataSafe
ERCB / BCOGC / SMER / NEB
compliant ERP & Pipeline Integrity
Management
www.DataSafe.ca
The engineers and managers of this pipeline project would go on to implement a
strict valve commissioning and pipe inspection procedure. As a result; welding
slag, dirt, rocks, and any other kind of debris was meticulously removed from
pipe sections before valve installation. Every valve was purged of factory grease
and replaced with a high quality synthetic lubricant and air tested to ensure that
the seat seals maintained their integrity. Eight years later, every commissioned
valve on this project retains perfect sealing integrity.
5. Routine maintenance
If the preceding four steps have been followed, the valve should be online with no
problems concerning sealing capability. In order to maintain the valve properly,
the operator will need to implement a scheduled routine of sealant system topups with synthetic lubricant. Typically, a new valve will require top-up more often
than a valve that has been in operation for one year or more. It is this first critical
year of operation that the valve seals sit tightest against the ball plug or gate slab
and lubricant is required to reduce the breakout torque during operation.
It is advised to top up the lubricant every time a valve is operated for the first year
in addition to a semi-annual full service schedule. It may seem excessive, but a
small investment in time and preventative maintenance on the front end could
potentially save hundreds of thousands, if not millions of dollars on the back end
taking into account pipe section isolation during emergency shutdowns.
Compared to the cost of an emergency valve body sealing job, a preventative
maintenance routine will quickly pay for itself.
Conclusion
Much of this information is not new to pipeline operators, yet thousands of valves
in every sector of the petroleum industry are scheduled for replacement every
year causing lost production. By taking a few simple steps like these ones above,
one could almost completely eliminate having to replace valves before their
service life expectancy. In combination with specialised sealants and pumping
equipment, it is conceivable that any given valve could stay in service indefinitely
and retain sealing integrity.
Appeared in issue: Pipelines International — December 2009
Categories: Integrity and Maintenance, Machinery & Equipment
Article permalink: http://pipelinesinternational.com/news/
5_simple_steps_to_total_valve_integrity/009339/
Share this article on the web:
Embed this article: <iframe width="500" height="170" frameborder="0" scrollin
Paste the above HTML code into your website to embed the article.
Do you have something to tell Pipelines International? Submit your news or
information here.
TELL A FRIEND
Your name:
Your email:
Your friend's name:
Your friend's email:
The article being sent:
http://pipelinesinternational.com/news/
5_simple_steps_to_total_valve_integrity/009339/
Message (optional):
http://pipelinesinternational.com/news/5_simple_steps_to_total_valve_integrity/009339/
1/26/2010
5 simple steps to total valve integrity — Pipelines International — The international pipel... Page 3 of 3


Please enter the word you see in the image below:
Send
RELATED ARTICLES
• US pipeline
company restructures
Wed, January 20, 2010
• KOC extends pipeline tender
deadline Tue, January 19, 2010
• FPL suspends pipeline
investment Tue, January 19, 2010
• Gulfstream awards compressor station expansion contract Tue, January 19,
2010
• TMK receives subsea pipeline certification Tue, January 19, 2010
• Dzhubga – Lazarevskoye – Sochi Pipeline remains on schedule Tue, January
19, 2010
• ETP raises capital for pipeline projects Tue, January 19, 2010
• Ohio River pipeline route on the cards Tue, January 19, 2010
• Gazprom establishes South Stream management department Thu, January
14, 2010
• Staying ahead of the pipeline professional pack; technical training courses
on offer in 2010 Wed, January 13, 2010
Home
Latest News
Events
Contact Us
Search
Photo Gallery
Magazine Issues
December 2009
September 2009
Archive
View all magazine issues
Subscribe to Pipelines International
Advertising
Media Kit
Editorial, Features and Deadlines
Ad Rates and Mechanical Details
A fresh voice
7 reasons to advertise
About
About the Publishers
About the Magazine
Legal
Privacy Policy
Disclaimer
Great Southern Press Sites
EcoGeneration
Emissions News
Gas Today
Pipeline Asia
PPO Pipeline, Plant & Offshore
Pipelines International
The Australian Pipeliner
Third Sector
Trenchless Australasia
Trenchless International
© 2009 Great Southern Press. All rights reserved. Contact Us.
http://pipelinesinternational.com/news/5_simple_steps_to_total_valve_integrity/009339/
1/26/2010
Download